1.Big and small gears are both made of alloy steel. 2.The integral tonifying heart is steel casting. 3.Transmission type can contain API-standard kellys and roller bushing of hexagonal kellys. Long and short slips are both appliable. 4.The rotary table is fully lubricated and reliably sealed. 5.The rotary table conforms to API Spec 7K specifications. It is allowable to use API logo.